The present invention relates to a method for entrance telephone communication utilizing public subscriber telephone networks.
SE, B, 451 422 and U.S. Pat. No. 4 987 589, for example, disclose how a public telephone network can be used for communication and operation purposes in an entrance telephone system. According to a preferred embodiment, it is also disclosed how a called party while maintaining secrecy, may accept or reject communication. However, a disadvantage is that rejected as well as accepted communication always results in a call charge, which, despite low installation costs for the system, often makes owners of property choose alternative solutions. For example. in U.S.A. a system is marketed under the slogan xe2x80x9cno telephone billxe2x80x9d, which is based on more or less conventional internal switching. Tenants may also be psychologically opposed to the fact that visitors/calls increase the cost of rent, since costs for the entrance telephone system is divided and added to the rent by the landlord, which means that tenants having few visitors/calls xe2x80x9csubsidizexe2x80x9dtenants having a large number of visitors/calls, e.g. doctors, dentists, and others having a high frequency of visitors. Coin or card operated entrance telephones have also been proposed; and all of the above indicates a major problem, and it is the object of the present invention to solve this problem.
The object of the present invention is to facilitate that call charges are divided more correctly, alternatively that call charges are eliminated/reduced (however, tenants may advantageously by means of the rent accept part of the fixed costs, since there are common functions; e.g. code lock is normally included), without imposing a complicated and more expensive administration for the landlord, for example by introducing a transaction memory, arranged to facilitate individual charging of the tenants. A further object of the present invention is to make it possible for tenants that permanently or temporarily wish to avoid entrance calls to completely avoid such calls by means of a programming operation and thus the non-fixed costs for entrance call charges, and with a totally protected integrity for all connected subscribers.
The method according to the present invention for entrance telephone communication utilizing public subscriber telephone networks is mainly characterized in that at least part of the subscribers connected to an entrance telephone system are arranged having a telecommunication subscription, or that the entrance telephone is arranged/connected in such a way, that the subscriber, or alternatively a sponsor/advertiser, is billed for received and switched through entrance telephone calls, preferably with the charges shown in the conventional telephone bill. According to the invention calls are preferably switched through and charged only after acceptance of the call from the called party, e.g. by dialling the digit xe2x80x9c1xe2x80x9d, and with disconnection, preferably without any call charge, if the called party does not accept the call, e.g. by dialling the digit xe2x80x9c2xe2x80x9d.